An occupant restraint system includes one or more sensor devices for sensing vehicle characteristics and/or occupant characteristics. The sensed characteristics are used to determine whether a vehicle occupant is to be restrained and/or a deployment profile for restraining the occupant. Examples of such sensor devices include a vehicle acceleration sensor, an occupant position sensor, and an occupant weight sensor. The restraint system also includes one or more actuatable restraint devices for restraining the occupant. Examples of such restraint devices include an air bag module, a knee bolster, and a seat belt pretensioner.
As the sophistication of occupant restraint systems has increased, the number and complexity of the sensor and restraint devices in a single vehicle has increased. In response to the increased number and complexity of devices, there has been a movement toward centralized control of the devices to reduce cost and to increase reliability of the overall restraint system.
Also, sometimes there is a need to replace one of the restraint system devices. For example, after deployment of an individual restraint device, the deployed restraint device must be replaced. Also, if a sensor device becomes inoperative, it must be replaced. The replacement device must be properly connected into the overall restraint system.
The changes in design approach and the need for ease in replacement for such restraint systems has brought about a need to design new arrangements for interconnecting individual devices to a central controller.